1. COMPUTER/TELEPHONY MESSAGING SYSTEMS
Voice-mail service systems permit a calling party to send a voice message to a called party without the assistance of another person. The called party is permitted to retrieve messages at will via his or her telephone without the assistance of another person. Conventional voice-mail service systems provide only audio access to the voice messages. That is, the messages can only be retrieved or created via a telephone, which means that a user must scroll sequentially through his or her message headers in voice mode by listening to the header information. This disadvantage is purportedly addressed by U.S. Pat. No. 5,003,577, Mar. 26, 1991, titled "Voice and Data Interface to a Voice-Mail Service System," which discloses a user access interface to a voice messaging (voice-mail) system. The disclosed system includes a voice channel and a data channel, the latter permitting the user to interact with the voice-mail service system via a video terminal or display-equipped computer and to print message headers on the terminal or display. The user can visually scan the headers and then listen to the messages or record new messages via the voice channel. An interface between the terminal and voice message system is provided by a "function" executing on the terminal. A data terminal interface "function" is executed on the voice-message service system. Users and their respective terminals are described as being interconnected by a private branch exchange (PBX) switching system. In addition, according to the patent, voice terminals are connected to the PBX by voice channels while data terminals are connected to the PBX by data channels. The patent states that the voice and data channels can be carried by separate physical links or a common link. For example, where the voice terminal is a standard telephone and the data terminal is a stand-alone PC, the voice and data channels could be carried, respectively, by a conventional telephone loop and a separate data link supporting the ISDN xB+D protocol. However, where the voice terminal is a digital telephone and the data terminal is a PC coupled to the digital telephone set, both the voice and data channels could be carried by a single link supporting the ISDN protocol.
One shortcoming of the system disclosed in U.S. Pat. No. 5,003,577 is that, if the user does not have a digital telephone, he or she must employ two separate communications links to concurrently access analog voice and digital data messages. Moreover, this system is believed to be inefficient in its use of "dumb" terminals; the complexity required to synchronize separate voice and data paths; and the cost associated with the additional port needed to provide voice and data paths. Furthermore, ISDN is not presently in general use, and so the system disclosed is limited to the extent it relies on ISDN.
2. THE UNISYS NETWORK APPLICATIONS PLATFORM
U.S. Pat. No. 5,133,004, Jul. 21, 1992, titles "Digital Computer Platform for Supporting Telephone Network Applications," discloses a "Network Applications Platform" (NAP) that is employed in a preferred embodiment of the present invention. The disclosure of this patent represents part of the background of the present invention, and thus is summarized below. The reader should review the patent itself for a complete description of the NAP. U.S. Pat. No. 5,323,450, dated Jun. 21, 1994, should also be reviewed for background.
The variety of telephone services currently available include call answer, call forward, voice store and forward, voice-mail, emergency number facilities, directory assistance, operator assistance, call screening, and automatic wake-up services. Such services had generally been provided by dedicated systems specifically designed for the service and the hardware environment in which the system was to be deployed, which made the systems inflexible and expensive. Following divestiture, the Bell Operating Companies (BOCs) and Independent Telephone Companies (Telcos), in devising ways to increase the return on their installed telephone networks, began to offer new services that integrated into, or interfaced with, the existing network, resulting in greater utilization of the network. The invention disclosed in U.S. Pat. No. 5,133,004 made it easier for the BOCs and Telcos to provide new services by removing the dependence on the telephone switch provider in implementing these new services. In particular, the Network Applications Platform, or NAP, was designed to interface with the telephone network and support application software deployed by the BOCs and Telcos to provide services they wanted to offer.
The NAP is a digital computer that interfaces with the network and is programmed with software providing the telephone network functionality required to support the new service-related applications. Such functionality includes detecting and reporting an incoming call from the network, initiating an outgoing call to the network, receiving a voice message from the network, sending a voice message to the network, collecting digits entered from the network, switching calls between channels, terminating calls, and detecting and reporting call termination.
The NAP includes a database including a voice file for storing predetermined digitized voice and tone messages to be applied to the network and voice messages received from the network to be re-applied thereto. The NAP is implemented on an A Series digital computer system commercially available from Unisys Corporation, Blue Bell, Pennsylvania, the assignee of the present invention. The NAP uses the standard parallel I/O processing capabilities, the Data Management System II (DMSII) and disk storage facilities and Direct I/O, as well as the communications capabilities such as Communication Management System (COMS) and Data Communications (DATACOM) of the A Series system. The applications communicate with the NAP through message-passing communication apparatus, such as the A Series COMS. The applications comprise a plurality of independent applications deployed by the telephone company to provide the desired services to the users.
The NAP includes three software modules collectively referred to as a Voice Network Management System (VNMS). The VNMS comprises an Application Interface Module (AIM), a Voice Message Management Module (VMMM), and a Network Interface Unit Manager (NIUM). The VNMS resides in main memory of the computer system on which the NAP is installed, i.e., the A Series system. The applications communicate with the AIM through the COMS via multiple dialogs, each representing a logically distinct sequence of related messages. The messages within each dialog occur in pairs, with each pair comprising an AIM Command from an application requesting the NAP to perform a function and a response from the AIM to the application with appropriate status information or data, such as keyed-in caller digits or message number identification Tokens.
The AIM is the point of communication between the NAP and the applications and directs the functionality of the NAP. Under the direction of the AIM, the VMMM controls sending and receiving digital voice messages between the NAP and the network. The AIM also communicates with the NIUM to receive digits from the network, such as DTMF digits; to receive status signals from the network; and to control call switching at the interface between the NAP and the network.
The NAP interfaces with the network through one or more Network Interface Units (NIUs). Each NIU comprises a computer-controlled, digital matrix switch that communicates with the lines and trunks of the network. The NIUs communicate with the voice message portion of the NAP via ports over a communication link comprising a conventional T1 digital voice link or trunk.
The NIUs communicate with the NIUM via communication apparatus, such as the A Series DATACOM. The communication links through the DATACOM from the NIUM to the NIUs control switching of ports so that any port can be connected to any other port. The NIUs include DTMF receivers that may be selectively connected to the ports of incoming calls under control of the NIUM to provide entered DTMF digits to the NIUM.
The VMMM controls sending and receiving digital voice messages to and from the network. The messages are stored on a disk. The VMMM communicates with the disk through an I/O processor system including an A Series I/O interface such as DMSII and Direct I/O. The I/O processor system communicates with the T1 digital voice link via an interface composed of one or more Voice Interface Modules (VIMs). The VMMM communicates with the VIMs via the I/O processor system which includes the standard A Series MLI (SDS 2323 7399) communication subsystem for effecting data transfers. Each of the VIMs is associated with a plurality of voice channels currently established by the system.
Predetermined voice messages, such as service offering prompts and instructions to callers, are stored on disk. These messages are accessed by the applications via the VMMM and transmitted over a voice channel through selected ports in the NIU. Voice messages from callers are stored on disk for re-transmission to the network under control of appropriate applications. The NIUM selects and connects the ports of the NIU under command of the applications and the VMMM controls the flow of the digital voice messages.
Central Office (CO) switches include the capability of detecting a predetermined number of ring-back or busy tones with respect to an incoming call and switching the incoming line to an outgoing line predetermined by the telephone company. Thus, for applications such as Call Answer, the CO can switch the call to a telephone number in the address space of the CO, for routing the call to the NAP so that the appropriate application can provide the service. Other services such as voice-mail and voice-store and forward use appropriate access telephone numbers in the address space of the CO to connect to the desired service. Based on configurable translation of information, such as the incoming port address and telephone number or other information transmitted to the NAP by the CO, the NIUM determines the appropriate application to utilize.
3. PROBLEMS WITH THE PRIOR ART
Unisys Corporation's Network Applications Platform, along with its suite of robust applications, can currently support subscribers using standard DTMF capable telephones and Group III capable facsimile machines connected to a Server through a public switched telephone network (PSTN). There is another group of Small Office/Home Office (SOHO) users that access a variety of database services from their home, office, or telecommuting PC. For a number of reasons (such as cost, logistics, or necessity), SOHO users are not attached to a local area network (LAN), and therefore must use a modem to gain access to the Server through the PSTN. These users also typically have a home telephone answering system or subscribe to a voice messaging service provided by a local telephone company.
The SOHO (and telecommuter) users represent a potential market for a service (referred to herein as a Universal Mailbox Service) that permits users to employ, via their PCs, the standard voice and facsimile messaging features currently available only via a telephone. A primary object of the present invention is to provide a system having the capabilities required to support SOHO users needing the flexibility and convenience of accessing voice, facsimile and data messaging services via a personal computer.